Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

This dataset provides aqueous nitrate+nitrite, aqueous manganese, aqueous iron, and total sulfate measurements in groundwater samples from 254 newly constructed private residential wells between 2014 and 2016. The study focuses on three geologically distinct regions of Minnesota: central, northwest, and northeast. These study regions were chosen due to their prevalent elevated As concentrations in drinking water. Each of the 254 wells were sampled in three rounds by the Minnesota Department of Health (MDH). The timing of the three sampling rounds was (1) immediately or shortly after well construction (round 1); (2) 3-6 months after initial sample collection (round 2); and (3) 12 months after initial sample collection...

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water...

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

Layered geospatial PDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features. This map is derived from GIS (geospatial information system) data. It represents a repackaging of GIS data in traditional map form, not creation of new information. The geospatial data in this map are from selected National Map data holdings and other government sources.

The table contains oxide and cation compositions of olivine grains from drill core of the Duluth Complex, Minnesota. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (wt%). The cations were calculated based on the oxide compositions and are reported in mole percent (mol%). Olivine is a magnesium iron orthosilicate mineral with the formula (Mg2+, Fe2+)2SiO4. Olivine forms a solid solution series with magnesium (Mg) at one end and iron (Fe) at the other. Forsterite (Mg2SiO4) is the magnesium endmember and fayalite (Fe2SiO4) is the iron endmember. Minor elements can substitute into the crystal structure, such as manganese (Mn) and nickel (Ni). To better understand...